1. Field of the Invention
The present invention relates to a projector and more particularly to the structure thereof.
2. Description of the Prior Art
Conventionally known is a projector which comprises electro-optical devices for forming an optical image of a light beam emitted from a light source in accordance with image information and a projection lens for expanding and projecting the image formed by the electro-optical devices, The projector of this type has been widely used for multi-media presentation in a conference, an academic meeting, or an exhibition.
More particularly, such a projector has a color beam splitting optical system interposed between the light source and the electro-optical devices. The color beam splitting optical system is accommodated in an optical component housing (inner case) designed to block ambient light, being adapted to split a light beam from the light source into beams of three colors (red, green, and blue) and then transmit the respective color beams to the electro-optical devices. Then, three color images of the respective color beams formed in the electro-optical devices are transmitted to a color beam combining optical system (prism) to be combined into a color image, thereafter being expanded and projected via the projection lens supported by a metallic support member (a head body).
The projector of this type may be kept installed in a conference room for making a presentation. However, it is often carried therein as required, or carried therefrom after a presentation to be stored somewhere else. Accordingly, it is necessary to improve the portability of the projector for ease of carrying it and thus it has been desired to reduce the size and weight of the projector.
However, a conventional projector is provided with a inner case in each of the upper and lower cases to accommodate and fix various types of optical components, in order to prevent shift of the optical axis of the optical components caused by considerable heat generated by the light source portion, the color beam combining optical system, the power supply unit and so on. However, this configuration is a stumbling block in the way of reducing the size and weight of the projector.
There is also another problem with the conventional projector. That is, it is difficult to take measures against EMI (Electro-Magnetic Interference) since circuits for processing feeble video signals at high speed and a light-source lamp causing strong noise are accommodated together in a narrow space.